1、 获取当前时间:
第一种:
Timestamp nowdate1 = new Timestamp(System.currentTimeMillis());
System.out.println("System.currentTimeMillis():"+nowdate1);
第二种:
Date date = new Date();
Timestamp nowdate2 = new Timestamp(date.getTime());
System.out.println("new Date():"+nowdate2)

2、 把 String类型转换 Timestamp:
String datestr = "2002-01-29 04:37:21.453";
Timestamp ts = Timestamp.valueOf(datestr);
System.out.println(ts);

3、 把 Timestamp 类型转换 String:
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Timestamp nowdate = new Timestamp(System.currentTimeMillis());
String datestr = sdf.format(nowdate);
System.out.println(datestr);
